Light-sensitive material for the bleaching out process



Patented Oct. 4, 1932 UNITED STATES PATENT omen:

BRUNO WEND'I, OF DFSSAU IN ANEALT, AND HANS BINOER, OF DESSAU-ZIEIBIGK IN ANIHLALT, GERMANY, ASSIGNOBS T0 AGFA ANSCO CORPORATION, OF IBINGHAMTON, NEW YORK, A. CORPORATION OF NEW XOR]! Lxcn'r-smrsr'rlyn MATERIAL ron'rnn BLEACHDIG our rnocnss a. Draining. Application filed June so, 19so,' sena1 No. 465,059, and in Germany July so, 1929.

Our present invention relates to the manufacture of light-sensitive materials and more particularly to light-sensitive substances asused in photographic bleaching-out processes and more particularly in the manufacture of photographic prints in natural colors/ Another object of our invention is the new light-sensitive layers obtainable by this process.

Our inventionis based on the observation that salts formed by an inorganic or organically substituted acid with an aromatic compound corresponding to the formula 0 as light-sensitive substances for bleachingout surfaces. In this-formula the aromatic nuclei may be substituted by halogen, the hydroxy, alkoxy, alkyl or carboxylic acid alkyl ester radicle.

I As dyes suitable according to our invention we enumerate the following 3-methyl-6-hydrbxy-Q-phenylxanthoxonium chloride 6-hydroxy-9-phenylxanthoxonium chloride 1 l i 1 see Journ. of the Chem. Society, London, vol. 99, page 548.

8-hydroxypheno-u.-fi-naphthoxanthoxonium chloride see Journ. of the Chem. Soc., London, vol. 97, page 1026. 1.2.7 trimethyl--hydroxybenzopyroxonium chloride 2-methyl-4-methoxy-7-phenylbenzopyroxonium methylsulfonate O-- --CH:

see Helvetica Chimica Acta, Vol. IX, page 494. see Liebigs Annalen, vol. 372, page 342. zmethylg,5 dihydmxy 7 pheny1benzopywxonium chloride 2.3.6.7.tetramethoxy-9-phenyl xunthoigonium chloride see Helvetica Chimica Acta, Vol. IX, page see Ber. der deutschen Chem. Ges., vol. 45, 496. page 2889, and Vol. 47, page 3052.

2-methy1-4.6-dii1ydl'oxy-7-phcnylbenzopyroxonium chloride 3.fi-dihydroxyxnnthoxonium chloride on so OH H0 -0 OH see Liebigs Annalen, vol. 372, page 351.

H I 0 CH3 3.G-Gihydroxy-Q-methyI-xanthoxonium chloride CH3 1 I O OH 90 Cl 7 see Berichte der deutschen Chem. Ges., vol.

34, page 1795. H0 2.Zgih idroxy-Q-orthocarbomethoxyphenyl xanthoxonium c see Liebigs Annalen, vol. 372, page 345 and page 348. 3.fi-dihydroxy-E)-phenomethyl-xanthoxonium chloride 000cm 95 H Ton o-k l] (I; I 100 see Berichte der deutschen Chem. Ges., vol. H0 0- 0H 38, page 1329, and Llebigs Annalen, vol. 372, P 7 see Journal fiir praktische Chemie (2) v01. 3.6-dihydroXy-Q-parachlorophenylxanthoxonium chloride 48 page 398. 105

4 Cl 3.6-dihydfoxy-Q-phenylxanthoxonium chloride H0 o OH J) 115 1 obtainable in an analogous manner as (IQ- n Others thereof See Liebigs Annalen i 0 figz 92; fl'flT'fj, Y cff Fi vol. 217, page 234 and Benchte der deutschen 3 W L} Cholmschen Gesellsehaft, v01. 42, page 870. vol. 42, page 870. 120

- 3.6411mvthoxy-9-orthocarbomethoxy-phenyl-xanthoxonlum 2.7-dlhydroxy-ILU411methyl-Uphonyl-xuuthoxonium chloride 011101100 on IhC kf 0 on, H30 0 0 00m The number of dyes being suitable forour new materials is not exhausted by the foregoing enumeration., Thus, we may use instead of the hydrochloric. salts oxonium salts of other acids. Or we may use corresponding compounds substituted'in the nucleus or esterified or etherified in the OH groups. As substituent there may be mentioned, for instance, alkyl or aryl residues.

The oxonium dyes of the kind described, generally, have a yellow color and are in the dark very stable when sensitized with oneof 'the usual sensitizers. When exposed tothe action of light, they bleach'very cleanly and yield pictures with pure white spots.

In preparing light-sensitive materials with the said dyes, we apply to a suitable support such as, for instance, paper or a celluloid film, a preparation containing about 1 to 3 mg. of the dye and 1 gram of a binding agent calculated on 100 square centimeters of the surface of the support. As a binding agent we may use, for instance, gelatin, nitrocellulose, acetyl cellulose or cellulose ethers, or preferably a mixture of. such binding agents from which one component dissolves the dye and the other, in which the dye is insbluble, swells used as a binding agent. An extraordinarily good fixation is obtainable by treating the light-sensitive materials with an alkali metal salt or borofluohydric acid, whereat a bor0-.

fluohydric salt of the oxonium dye is formed which is insoluble in the solvents used for the removal of the sensitizer. Thus, a fading or blurring of the color pictures is avoided.

From the following example serving to illustrate our invention it may be seen how to obtain a bleaching-out layer useful'in manufacturing a three-color picture by a printing process.

Ezvample.A mixture containing 15 grs.of a solution of ethylbenzylcellulose of 5 per cent strength in ethanol and benzene'in the ratio 1 :1, and 7.5 g'rs.of a solution of nitrocellulose in ethylether and ethanol mixed in the ratio 3 1 is diluted with 100cm. ofbenzene, 3 ccm. of ethlyether and 12 ccm. of ethanol.

To this solution are added 3.5 ccm. of a solution of the yellow dye dissolved in ethanol to form a solutionof 01/250 strength 2.5 ccm. of a solution of the purple die I onemiiiln one 2 dissolved in ethanol to form likewise a solution of 91/250 strength, 5 com. of the blue,

green dye dissolved in ethanol to form a solution of 71/500 strength and finally 5 com. of an alcoholic solution of diethylallythiourea of 10 per cent strength. The solution, thus prepared, is poured on 400 sq. cm. of baryta paper and dried.

From the sensitized paper thus obtainable multi-color prints are made by exposing them 1 behind a multi-colored transparency to th e action of light. As a transparency we may use, for instance, a screen plate or a multicolor print on paper made transparent, if v necessary, by a suitable treatment with oil.

Thus, the different colors are printed in one operation. Multicolor pictures are likewise obtainable. by exposing the bleaching-out layer described subsequently behind black and white silver-pictures onwhichthe singlecolorsensations are registered while using simultaneously a correspondingly colored screen. The print obtained is'fixed by a treatment with a. solvent mixture containing benzine and anisol in the ratio 3: 1 removing the sensitizer from the layer.

In the claims following hereafter, we indicate for the sake of clarity the oxonium salts 7 .in question as salts formed with the aid of salts of otherinorganic or organically substihydrochloric acid. As :mentioned above,

tuted acids show the same behavior and are intended to be covered by the claims as equivalents. The same holds true with regard to homologous compounds having an analogous structure.

What we claim is:

1. Light-sensitive materials for the bleaching-out process containing an oxonium salt of generally yellow color corresponding to the general formula:

ortho phenylene, ortho naphthylene, and

substitution products of these aromatic radicles bearing an alkyl, a hydroxy or methoxy group, X meaning H, methyl, benzyl, phenyl, chlorophenyl, phenylcarboxylic acid methyl ester radicle, Y meaning H, OH, methoxy.

2. Light-sensitive materials for the bleaching-out process containing an oxonium salt of generally yellow color corresponding to the general formula:

R meaning \CH \{11 ?|JOHz (LEE, -CHa, C-CHa, I

Y 0 Y, a X meaning H, methyl, benzyl, phenyl, chlorophenyl, phenylcarboxylic acid methylester radicle, and Y meaning methyl, methoxy.

4. Light-sensitive materials for the bleaching-out process containing an oxonium salt of generally yellow color corresponding to the general formula:

X meaning H, methyl, benzyl, phenyl, chlorophenyl, phenylcarboxylic acid methyl ester radicle, and Y meaning OH, methoxy.

5. Light-sensitive materials for the bleaching-out process containing an oxonium salt of generally yellow color corresponding to the general formula:

Y Y n fl Y \O Y Y meaning H, OH, methyl, methoxy. 6. Llght-sensltive materials for the bleachlng-out process containing an oxonium salt of generally yellow color corresponding to the general formula Y meaning H, methyl, OH, methoxy.

7 Light-sensitive materials for the bleaching-out process containing the oxonium salt of yellow color corresponding to the formula:

8. Light-sensitive materials for the bleaching-out process containing the oxonium salt of yellow color corresponding to the formula:

9. Light-sensitive materials for the bleaching-out process containing the oxonium salt of yellow color corresponding to the formula:

CHJO Z 0011: I

In testimony whereof, we afix our signatures.

' BRUNO WENDT. HANS BINCER. 

